Rough Electrical problem with MANY effects..

[Vancefish]

I bought this 91 SE a couple of years ago. It's much nicer then my previous 92LX.

However I'm having the strangest set of electrical issues that seem to be related.

First all my tail lights work in Reverse, but once in Drive the drivers side trunk mount tail light goes out. IF the headlights are on it registers on the dash, but not if they are off.

Next, IF I'm pressing on the brake peddle all the dash light dim. But not if the headlights are on.

Lastly IF the headlights are on? The initial engagement of the transmission from a stop slips. It feels like the tire slips on ice, but there is no wheel rotation.

It seams to mainly stem from the Brake lights, or maybe the brake peddle sensor??

I'm just hoping someone can say it is.. ____!

[accordztech]

Wow, you got quite a few gremlins in your car.

First off I would take out each rear bulb and make sure its the right bulb for the socket. I seen people use dual filament with single filament sockets somehow and it causes weird issues. Also look for corrosion or rust in the sockets.

Also look in the trunk where the bulbs are and see if someone screwed with the wiring or ran wires around there. Also check the sensor for the bulb out feature and see if its been rusted or water damage.

As for the brake pedal making everything dim, you may have issues in the back of the car. If there is lots of corrosion on the bulb terminals and you step on the brakes, you may be seeing resistance somehow...OR it can be a battery/alternator/ground issue. Grab a multimeter at the battery and test it with the car running etc...and test it when you hit the brakes and note the voltage.

If your lights are on and your tranny slips, then im lost on that. They shouldn't be related in my opinion. But do check all the factory grounds that you can see to see that they aren't rusted up or corroded. Check the negative terminal on the battery mainly the portion inside the wire insulation to make sure you see copper wires, not white crap.

[toycar]

Bad ground is causing a drop in voltage, which creates a spike in amperage. This is why the car hesitates. It's not your tranny, the car stutters when the lights come on because they are forcing the spike in amperage. They are drawing enough current basically. That's why they seem related.

You probably have a bad ground somewhere. It may be causing all of your issues. It's also possible your rear bulb sockets have corroded and caused some issues. Remove the bulbs and signs of this should be pretty obvious

When all else fails, bust out a multi meter and measure resistance and try to identify that way. Most likely a bad socket is causing this issue. But, everything could also be related to one bad ground.


Good luck, electrical problems are the worst.

[EsperHamid]

if you own a phone with a camera, be sure to take pictures of each and every wire you want to work on, just in case ,,,, electrical problems are not as hard as idle problems and vacuum leaks but the need a lot of memory ... your camera phone is your friend.

I don't mean to highjack the thread but I have the small ground going from the power steering bracket to the engine valve cover is toasted from power steering fluid leak ... what size of wire gauge should I use to replace it !?!!

[accordztech]

if you own a phone with a camera, be sure to take pictures of each and every wire you want to work on, just in case ,,,, electrical problems are not as hard as idle problems and vacuum leaks but the need a lot of memory ... your camera phone is your friend.

I don't mean to highjack the thread but I have the small ground going from the power steering bracket to the engine valve cover is toasted from power steering fluid leak ... what size of wire gauge should I use to replace it !?!!

I think 10-12 is fine. Anything thicker is ok.

[Vancefish]

Thanks all! Sorry I didn't reply sooner. Rough week.

I'll go through all of these over the weekend. I'll start with the ground wires I know about. Then go through the tail lights.

I need to get this resolved before I need headlights to get home at night.

[Vancefish]

I went through the main ground wire to the block and the battery terminals of course. That looks to have helped because the car will stay in Cruse with the headlights on now.

As for the tail lights? The connectors on the bulb itself had melted (made purely out of solder it seems). Then pooled into a jumper. A new bulb and the tail light issue is solved as well.

Only remaining issue is the lights on the dash (like the seat belt light the never turns off with the "auto seat belt" disconnected), dims a little when I press on the gas. Any ideas on that one??

Thanks again for all the help!